1. Technical Field
The present invention relates to a liquid crystal display device and to an electronic apparatus.
2. Related Art
Transflective liquid crystal display devices in the related art have a problem in that a viewing angle is narrow in transmissive display. The reason is that, since a transflective sheet is provided on an inner surface of a liquid crystal cell to prevent the occurrence of parallax, reflective display is performed by using only one polarizing plate provided on an observer side, which results in a low degree of flexibility in the optical design. Therefore, in order to solve this problem, M. Jisaki et al. have proposed a liquid crystal display device using vertical-alignment-type liquid crystal, as disclosed in “Development of transflective LCD for high contrast and wide viewing angle by using homeotropic alignment,” M. Jisaki et al., Asia Display/IDW'01, pp. 133 to 136 (2001). The liquid crystal display device has the following three features:
(1) A ‘VA (vertical alignment) mode’ is used in which liquid crystal molecules having negative dielectric anisotropy are vertically aligned with respect to substrates in an initial state, and are then inclined when a voltage is applied;
(2) A ‘multi-gap structure’ is used in which the thickness (cell gap) of a liquid crystal layer in a transmissive display region is different from that in a reflective display region (for example, see Japanese Unexamined Patent Application Publication No. 11-242226); and
(3) An ‘alignment dividing structure’ is used in which each transmissive display region is formed in the shape of a regular octagon, and a projection is provided at the center of the transmissive display region on a CF substrate to make the liquid crystal molecules incline in all directions in the transmissive display region.
In the liquid crystal display device described in the above-mentioned related art, when alignment division is performed as described in the third feature, it is important to accurately control the liquid crystal molecules to be arranged in an intended alignment state. However, in an active matrix liquid crystal display device using thin film transistors (TFTs) or thin film diodes (TFDs) as switching elements, a strong electric field generated from these switching elements or signal lines connected thereto acts on a liquid crystal layer to cause alignment disorder of the liquid crystal. Therefore, in order to remove the effects of the strong electric field around the elements, an overlayer structure has been suggested in which an insulating film is formed to cover a layer including the switching elements and electrodes are formed on the insulating film.
The overlayer structure makes it possible to prevent the alignment disorder of the liquid crystal due to the strong electric field caused by the switching elements. However, in the overlayer structure, the electrodes are electrically connected to the switching elements through contact holes formed in the insulating film. As a result, concave portions corresponding to the contact holes are formed in a surface of a substrate coming into contact with the liquid crystal, and thus the thickness (cell gap) of the liquid crystal layer is larger than a design value in the concave portion. Thus, this structure has a problem in that display light appears to be colored.